Solve for $x$ and $y$ using substitution. ${-4x+3y = -12}$ ${x = 2y-7}$
Explanation: Since $x$ has already been solved for, substitute $2y-7$ for $x$ in the first equation. ${-4}{(2y-7)}{+ 3y = -12}$ Simplify and solve for $y$ $-8y+28 + 3y = -12$ $-5y+28 = -12$ $-5y+28{-28} = -12{-28}$ $-5y = -40$ $\dfrac{-5y}{{-5}} = \dfrac{-40}{{-5}}$ ${y = 8}$ Now that you know ${y = 8}$ , plug it back into $\thinspace {x = 2y-7}\thinspace$ to find $x$ ${x = 2}{(8)}{ - 7}$ $x = 16 - 7$ ${x = 9}$ You can also plug ${y = 8}$ into $\thinspace {-4x+3y = -12}\thinspace$ and get the same answer for $x$ : ${-4x + 3}{(8)}{= -12}$ ${x = 9}$